Speed-flow relationships on motorways

Frank Kelly

The Freeway-Congestion Paradox.
C. Chen, K. Petty, A. Skabardonis and P. Varaiya.
Transportation Research Record 1748, 96-102, 2001.

Data on the UK road network is beginning to become available to researchers:
Motorway Incident Detection and Automatic Signalling (Midas) Data
Traffic Information Database

Background pointers:
CMI's National Transport Data Framework
Transport Data Needs Project
Traffic Information Highway
Vision 2030 - a portfolio of transport visions
Changing face of transportation
Transport Research Knowledge Centre
Transport Direct